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arXiv · 1310.8427

Origin of two-dimensional electron gases at oxide interfaces: insights from theory

N C Bristowe·Philippe Ghosez·P B Littlewood·Emilio Artacho
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Abstract

The response of oxide thin films to polar discontinuities at interfaces and surfaces has generated an enormous activity due to the variety of interesting effects it gives rise to. A case in point is the discovery of the electron gas at the interface between LaAlO3 and SrTiO3, which has since been shown to be quasi-two-dimensional, switchable, magnetic and/or superconducting. Despite these findings, the origin of the two-dimensional electron gas is highly debated and several possible mechanisms remain. Here we review the main proposed mechanisms and attempt to model expected effects in a quantitative way with the ambition of better constraining what effects can/cannot explain the observed phenomenology. We do it in the framework of a phenomenological model for understanding electronic and/or redox screening of the chemical charge in oxide heterostructures. We also discuss the effect of intermixing, both conserving and non-conserving the total stoichiometry.

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N C Bristowe, Philippe Ghosez, P B Littlewood, Emilio Artacho. 2014-03-20. Origin of two-dimensional electron gases at oxide interfaces: insights from theory. https://doi.org/10.1088/0953-8984%2F26%2F14%2F143201

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